List of Articles
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Open Access Article
1 - Tourmaline genesis in the metamorphic and magmatic rocks of Gasht-e- Rudkhan district (Gasht metamorphic Complex, West of Rasht)
Maryam Mohammadi Abbas Asiabanha Kazem GholizadehGasht metamorphic complex crops out in the Talesh Mountains (Western Alborz). This complex mainly consists of metapelitic and granitic rocks. Tourmaline is prevalent as an accessory phase within these rocks. In schist samples, dravitic tourmaline is abundant as nucleati MoreGasht metamorphic complex crops out in the Talesh Mountains (Western Alborz). This complex mainly consists of metapelitic and granitic rocks. Tourmaline is prevalent as an accessory phase within these rocks. In schist samples, dravitic tourmaline is abundant as nucleation component and fine size, and displays compositional zoning. Dravitic tourmaline of gneissic samples are coarser and homogenous. Tourmaline of the migmatites are restricted to both leucosome and melanosome parts. Brown tourmalines of garnet-bearing melanosome are magnesiofoitite in composition and similar to the other mafic phases of melanosome, indicate a residuum nature. However, dravitic tourmalines of the garnet – free melanosome are coarse crystalline and have grown over biotite with green pleochroism. The composition of the leucogranite tourmalines are schorlitic and they become dravitic toward rims. Different types of replacement are observed in the tourmaline composition of Gasht complex. According to the compositional signatures, metapelites tourmaline were formed mainly under metamorphic conditions, while the one of the leucogranites have been formed in the magmatic conditions. Probably B-bearing fluids of Gasht complex in the high grade metamorphism caused lowering of the temperature of water-bearing solidus of granite. This resulted in facilitating of migmatitization process. Furthermore, boron element caused decreasing of leucosome viscosity, mobilization and easier fractionation of melt from melanosome and creation of adjacent leucogranites. Manuscript profile -
Open Access Article
2 - The Study of alteration, mineralization, and fluid inclusion in the Howz-e-Sefid zinc-lead deposit (Central Iran)
The Howz-e-sefid zinc-lead deposit is located 17 km northeast of Ardakan town in the central Iran tectonic zone. Host rock of this deposit is lower Cretaceous dolomitized carbonate rocks. In this area there are three major rock units. The Sangestan Formation as the lowe MoreThe Howz-e-sefid zinc-lead deposit is located 17 km northeast of Ardakan town in the central Iran tectonic zone. Host rock of this deposit is lower Cretaceous dolomitized carbonate rocks. In this area there are three major rock units. The Sangestan Formation as the lowest unit, is composed of shale and siltstone with calcarenitic interbeded layers. This unit is overlain by ankeritic massive dolomite and dolomitic limestone of the Taft Formation. The Abkouh Formation at the top, is composed of cherty or argillaceous limestone with massive reefal limestone. The host rock of deposit in the lower Cretaceous carbonate horizon along with other geological evidence indicate that this deposit has been primarily formed similar to the Mississipi Valley-type deposits. This conditions include carbonate and evaporatic sequences, special hydrothermal dolomitized horizons, lack of the effects of igneous intrusions and the presence of the important controling faults. Based on the observations, it can be concluded that the primary ores have been of the sulphide type including sphalerite, galena and pyrite. Due to their exposure to superficial oxidizing conditions and undergoing changes, the primary sulphide ores, have been converted into nonsulphide ore body. As a result, the primary sulphide ores have been changed into secondary minerals such as hemimorphite, smithsonite, cerusite and anglesite. In many cases, the nonsulphide minerals established in the structural fractures and fissures, shows the colloform texture. Therefore, it can be accepted that this type of minerals were formed under the effect of low temperature hydrothermal fluids.There are two types of fluid inclusions (type I: L and type II: L+V) in the carbonaceous ore bearing veins. On the basis of microthermometric study, the homogenization temperatures is between 150-260 °C. The salinity of fluid inclusions is low to intermediate (0.33-14.26 wt. % NaCl equivalent). Heating depressurization due to reduced pressure to boiling with low CO2 bearing fluid (0.62-0.98 gr/cm3) is the main mechanism of deposition. Based on evidence such as the nonhomoginity in filling degree of fluid inclusions, existence of a few vapor-rich phase shows boiling of ore fluid in faulted and fracture zones. Manuscript profile -
Open Access Article
3 - The Study of alteration, mineralization, and fluid inclusion in the Howz-e-Sefid zinc-lead deposit (Central Iran)
Mansor Adelpour godratollah Rostami PaydarThe Howz-e-sefid zinc-lead deposit is located 17 km northeast of Ardakan town in the central Iran tectonic zone. Host rock of this deposit is lower Cretaceous dolomitized carbonate rocks. In this area there are three major rock units. The Sangestan Formation as the lowe MoreThe Howz-e-sefid zinc-lead deposit is located 17 km northeast of Ardakan town in the central Iran tectonic zone. Host rock of this deposit is lower Cretaceous dolomitized carbonate rocks. In this area there are three major rock units. The Sangestan Formation as the lowest unit, is composed of shale and siltstone with calcarenitic interbeded layers. This unit is overlain by ankeritic massive dolomite and dolomitic limestone of the Taft Formation. The Abkouh Formation at the top, is composed of cherty or argillaceous limestone with massive reefal limestone. The host rock of deposit in the lower Cretaceous carbonate horizon along with other geological evidence indicate that this deposit has been primarily formed similar to the Mississipi Valley-type deposits. This conditions include carbonate and evaporatic sequences, special hydrothermal dolomitized horizons, lack of the effects of igneous intrusions and the presence of the important controling faults. Based on the observations, it can be concluded that the primary ores have been of the sulphide type including sphalerite, galena and pyrite. Due to their exposure to superficial oxidizing conditions and undergoing changes, the primary sulphide ores, have been converted into nonsulphide ore body. As a result, the primary sulphide ores have been changed into secondary minerals such as hemimorphite, smithsonite, cerusite and anglesite. In many cases, the nonsulphide minerals established in the structural fractures and fissures, shows the colloform texture. Therefore, it can be accepted that this type of minerals were formed under the effect of low temperature hydrothermal fluids.There are two types of fluid inclusions (type I: L and type II: L+V) in the carbonaceous ore bearing veins. On the basis of microthermometric study, the homogenization temperatures is between 150-260 °C. The salinity of fluid inclusions is low to intermediate (0.33-14.26 wt. % NaCl equivalent). Heating depressurization due to reduced pressure to boiling with low CO2 bearing fluid (0.62-0.98 gr/cm3) is the main mechanism of deposition. Based on evidence such as the nonhomoginity in filling degree of fluid inclusions, existence of a few vapor-rich phase shows boiling of ore fluid in faulted and fracture zones. Manuscript profile -
Open Access Article
4 - Experimental modeling of migration in Shekarab active fault system (North Birjand)
Mehdi Yosefi Mohammad Mahdi Khatib Ebrahim GholamiThe Shekarab fault system, located in the north of the Birjand city, has fault scarps parallel to main fault. Due to the structural features, mechanism of fault trends in the region, fault-related folding and the occurrence of the migration from the north to the south a MoreThe Shekarab fault system, located in the north of the Birjand city, has fault scarps parallel to main fault. Due to the structural features, mechanism of fault trends in the region, fault-related folding and the occurrence of the migration from the north to the south at Shekarab fault, modeling is done for the geometric pattern of the fault propagation, which is in accordance with the Shekarab fault zone. In this model, new scarps are formed in the footwall of the previous scarps. According to the results of modeling, the most important factor for creating alternate scarps is the north-south compression in the Shekarab thrust. At each step, by increasing the amount of shortening, the emergence of new faults are observed so that the first thrust is created on the northern side of the Shekarab zone and subsequent faults are created by increasing the amount of shortening up to a maximum of 58%, on the southern side of the zone and on the footwall of the previous faults. In this modeling, the slope of the thrusts is created in four stages of shortening varying between 60-65 degrees, which is comparable with the actual slope of the Shekarab faults of 70 degrees. According to the experimental results, the sequence of thrust creation in each modeling stage is consistent with the sequence of thrust in the Shekarab zone and with the north-south migration of the fault. According to the geometry of thrusts and back-thrust, the model of formation of structures in this fault zone is the foreland breaking sequence model so that the branches of the thrust originate from a point. Manuscript profile -
Open Access Article
5 - Bioremediation potential of oil-contamination in aquifer of around Shazand Oil Refinery
Abdolreza Vaezi Sanaz QobadianIn this research, bioremediation potential of the aquifer located beneath Shazand Oil Refinery Company was evaluated according to the hydrochemical characteristics of groundwater samples. Groundwater quality determined by sampling from different locations and specifying MoreIn this research, bioremediation potential of the aquifer located beneath Shazand Oil Refinery Company was evaluated according to the hydrochemical characteristics of groundwater samples. Groundwater quality determined by sampling from different locations and specifying some hydrochemical parameters such as EC, DO, T, pH as well as concentration of the major ions (Ca2+, Mg2+, (K++Na+), SO4-2, Cl-, (CO3-2+HCO3-)), some heavy metals (Fe+2, Mn+2) and nutrients (N-3, SO4-2). The results revealed that the amount of pH and EC provided a suitable condition for biodegradation of hydrocarbon contaminants. Dissolved oxygen concentration of the samples shows a suitable condition for aerobic biodegradation, however, there is not an optimum condition based on the average temperature and nutrient concentration. Carbon to nitrogen and to phosphorus ratios and also nitrogen to phosphorus ratio are not suitable in the optimum range. It means that in the case of site remediation the aquifer of the area has not adequate ability to conduct natural bioremediation and so an enhanced remediation operation will be inevitable. Manuscript profile -
Open Access Article
6 - Reconstructing physicochemical attributes using chemistry of biotite and chlorite in the Keder porphyry copper deposit, Kerman Cenozoic magmatic arc
Majid Heydari Alireza Zarasvandi Mohsen Rezaei عادل ساکی Sina AsadiThe Keder porphyry copper deposit is located 14 km SW of Dehej in the north-eastern of Kerman Cenozoic magmatic arc. It is associated with diorite to quartz diorite intrusions. Considering the important role of oxygen fugacity, halogen content, and temperature in the mi MoreThe Keder porphyry copper deposit is located 14 km SW of Dehej in the north-eastern of Kerman Cenozoic magmatic arc. It is associated with diorite to quartz diorite intrusions. Considering the important role of oxygen fugacity, halogen content, and temperature in the mineralization efficiency of porphyry systems, the aims of present research is the investigation of these physicochemical attributes in the magmatic stage, as well as potassic alteration of Keder porphyry using biotite and chlorite chemistry. Compared with chlorite, biotite has high SiO2, K2O, TiO2 concentrations. On the other hand, Al2O3 has highest concentration in chlorite. The depletion of K2O and SiO2 are related to the formation of adularia and K-feldspar accompanying with the breakdown of biotite to chlorite. Biotite chemistry shows that the Keder intrusion is calc-alkaline in nature. Based on FeO/FeO+MgO vs MgO diagram, biotites from Keder intrusion plot within the mantle source (M) and to a lesser extent in the crustal materials field. Using the Si vs Fe2+/Fe2+ +Mg2+ diagram, secondary chlorites that replaced biotite plot collectively within clinochlore composition. Oxygen fugacities of Keder deposit occur in HM-NNO area. The investigation of geothermometry on biotites and chlorite in the Keder porphyry copper deposit shows a temperature range between 516-680° C and 180.19-369.87° C respectively. The log fH2O/fHF and log fH2O/fHCl values range between 4.57-5.77 and 4.34-4.62 that show water content is more than halogen content in Keder intrusion. According to XFe and XMg vs. XF/XOH and XCl/XOH, Cl fugacity was similar in Keder porphyry copper deposit. Finally, it seems that high temperature together with prevailing of high oxygen fugacities during potassic alteration (onset of sulfide mineralization) could be considered as important factors on low grade mineralization at Keder deposit. Manuscript profile -
Open Access Article
7 - The Study of geochemical behavior of major and rare earth elements of garnet in the Darreh Vali pegmatites (North-east Boroujerd, Sanandaj-Sirjan zone)
The pegmatites of Darreh Vali region is located in the north-east of Boroujerd which is a part of Sanandaj-Sirjan zone. In the Darreh Vali area, granodiorite bodies are cut by small pegmatitic dykes with NW–SE trend. The mineralogy of studied pegmatites consists of quar MoreThe pegmatites of Darreh Vali region is located in the north-east of Boroujerd which is a part of Sanandaj-Sirjan zone. In the Darreh Vali area, granodiorite bodies are cut by small pegmatitic dykes with NW–SE trend. The mineralogy of studied pegmatites consists of quartz, alkali-feldspar (orthoclase and microcline), plagioclase, muscovite, garnet (almandine-spessartin), andalusite, tourmaline, and apatite. Chondrite-normalized patterns of the Darreh Vali pegmatite are characterized by low enrichments of LREE relative to HREE (LaN/YbN=1.76-4.04), with a relatively flat HREE distribution, and a strong negative Eu anomaly (Eu/Eu* =0.20-0.54). Major element chemistry of garnets in these pegmatites indicates a compositional zoning with decreasing MnO and increasing FeO from core towards the rim. In the case of the Darreh Vali pegmatites, all garnet crystals contain low CaO (0.15 to 0.29 wt.%) and high MnO (10.27 to 13.18 wt.%), which are similar to magmatic garnets from pegmatitic melts. On the MnO+CaO versus FeO+MgO (in wt. %) diagram, the composition of garnets shows that they probably crystallised in contact zones of pegmatite vein and from less evolved melts. LA-ICP-MS analyses show that analysed garnets have a high HREE, low LREE contents, and strong negative Eu anomaly (Eu/Eu*=0-0.41) in the core along with positive Eu anomaly (Eu/Eu*=0-3.22) at the rim. Y, HREE, Ti, Zr, Nb, Ta, Hf, U and Mn decrease from core to rim. These core-to-rim elemental variations are attributed to increasing fluid-phase and H2O activity in magma, along with increasing magma fractionation. REE patterns and Eu anomalies in zoned garnets suggest that they probably formed in reducing to oxidizing conditions. Manuscript profile -
Open Access Article
8 - The Study of geochemical behavior of major and rare earth elements of garnet in the Darreh Vali pegmatites (North-east Boroujerd, Sanandaj-Sirjan zone)
The pegmatites of Darreh Vali region is located in the north-east of Boroujerd which is a part of Sanandaj-Sirjan zone. In the Darreh Vali area, granodiorite bodies are cut by small pegmatitic dykes with NW–SE trend. The mineralogy of studied pegmatites consists of quar MoreThe pegmatites of Darreh Vali region is located in the north-east of Boroujerd which is a part of Sanandaj-Sirjan zone. In the Darreh Vali area, granodiorite bodies are cut by small pegmatitic dykes with NW–SE trend. The mineralogy of studied pegmatites consists of quartz, alkali-feldspar (orthoclase and microcline), plagioclase, muscovite, garnet (almandine-spessartin), andalusite, tourmaline, and apatite. Chondrite-normalized patterns of the Darreh Vali pegmatite are characterized by low enrichments of LREE relative to HREE (LaN/YbN=1.76-4.04), with a relatively flat HREE distribution, and a strong negative Eu anomaly (Eu/Eu* =0.20-0.54). Major element chemistry of garnets in these pegmatites indicates a compositional zoning with decreasing MnO and increasing FeO from core towards the rim. In the case of the Darreh Vali pegmatites, all garnet crystals contain low CaO (0.15 to 0.29 wt.%) and high MnO (10.27 to 13.18 wt.%), which are similar to magmatic garnets from pegmatitic melts. On the MnO+CaO versus FeO+MgO (in wt. %) diagram, the composition of garnets shows that they probably crystallised in contact zones of pegmatite vein and from less evolved melts. LA-ICP-MS analyses show that analysed garnets have a high HREE, low LREE contents, and strong negative Eu anomaly (Eu/Eu*=0-0.41) in the core along with positive Eu anomaly (Eu/Eu*=0-3.22) at the rim. Y, HREE, Ti, Zr, Nb, Ta, Hf, U and Mn decrease from core to rim. These core-to-rim elemental variations are attributed to increasing fluid-phase and H2O activity in magma, along with increasing magma fractionation. REE patterns and Eu anomalies in zoned garnets suggest that they probably formed in reducing to oxidizing conditions. Manuscript profile -
Open Access Article
9 - The Study of geochemical behavior of major and rare earth elements of garnet in the Darreh Vali pegmatites (North-east Boroujerd, Sanandaj-Sirjan zone)
Somaye Rahmani Zahra Tahmasbi Xin Ding Ahmad Ahmadi KhalagiThe pegmatites of Darreh Vali region is located in the north-east of Boroujerd which is a part of Sanandaj-Sirjan zone. In the Darreh Vali area, granodiorite bodies are cut by small pegmatitic dykes with NW–SE trend. The mineralogy of studied pegmatites consists of quar MoreThe pegmatites of Darreh Vali region is located in the north-east of Boroujerd which is a part of Sanandaj-Sirjan zone. In the Darreh Vali area, granodiorite bodies are cut by small pegmatitic dykes with NW–SE trend. The mineralogy of studied pegmatites consists of quartz, alkali-feldspar (orthoclase and microcline), plagioclase, muscovite, garnet (almandine-spessartin), andalusite, tourmaline, and apatite. Chondrite-normalized patterns of the Darreh Vali pegmatite are characterized by low enrichments of LREE relative to HREE (LaN/YbN=1.76-4.04), with a relatively flat HREE distribution, and a strong negative Eu anomaly (Eu/Eu* =0.20-0.54). Major element chemistry of garnets in these pegmatites indicates a compositional zoning with decreasing MnO and increasing FeO from core towards the rim. In the case of the Darreh Vali pegmatites, all garnet crystals contain low CaO (0.15 to 0.29 wt.%) and high MnO (10.27 to 13.18 wt.%), which are similar to magmatic garnets from pegmatitic melts. On the MnO+CaO versus FeO+MgO (in wt. %) diagram, the composition of garnets shows that they probably crystallised in contact zones of pegmatite vein and from less evolved melts. LA-ICP-MS analyses show that analysed garnets have a high HREE, low LREE contents, and strong negative Eu anomaly (Eu/Eu*=0-0.41) in the core along with positive Eu anomaly (Eu/Eu*=0-3.22) at the rim. Y, HREE, Ti, Zr, Nb, Ta, Hf, U and Mn decrease from core to rim. These core-to-rim elemental variations are attributed to increasing fluid-phase and H2O activity in magma, along with increasing magma fractionation. REE patterns and Eu anomalies in zoned garnets suggest that they probably formed in reducing to oxidizing conditions. Manuscript profile -
Open Access Article
10 - Geometric and kinetic analysis of Khaneh Sorkh folding in the Lorestan region, Zagros Folded– Thrust Belt
This research has been carried out in order to understand geometric and kinetic analysis of the khaneh Sorkh folding and its structural style. Khaneh Sorkh folding is a long and narrow anticline that is formed due to sleep in the Garau Formation which is located in the MoreThis research has been carried out in order to understand geometric and kinetic analysis of the khaneh Sorkh folding and its structural style. Khaneh Sorkh folding is a long and narrow anticline that is formed due to sleep in the Garau Formation which is located in the Lorestan region. The Garau Fomation is the intermediate detachment layer in the Lorestan. In order to carry out geometric analysis, three structural cross sections were drawn perpendicular to the axial surface trace on this anticline. Thus, based on the analysis of the geometry of cross sections and comparing parameters with variety of models, it could be suggested that the Khaneh Sorkh Anticline is a detachment fold in the thrust fault-related folds. Finally,geometry of faulted detachment fold and analysed kinetic evolution is valid for Khaneh Sorkh Anticline based on the proposed model. Manuscript profile -
Open Access Article
11 - Geometric and kinetic analysis of Khaneh Sorkh folding in the Lorestan region, Zagros Folded– Thrust Belt
Khatoon Pirdadi Aziz Rahimi Mohamad Mahdi FarahpourThis research has been carried out in order to understand geometric and kinetic analysis of the khaneh Sorkh folding and its structural style. Khaneh Sorkh folding is a long and narrow anticline that is formed due to sleep in the Garau Formation which is located in the MoreThis research has been carried out in order to understand geometric and kinetic analysis of the khaneh Sorkh folding and its structural style. Khaneh Sorkh folding is a long and narrow anticline that is formed due to sleep in the Garau Formation which is located in the Lorestan region. The Garau Fomation is the intermediate detachment layer in the Lorestan. In order to carry out geometric analysis, three structural cross sections were drawn perpendicular to the axial surface trace on this anticline. Thus, based on the analysis of the geometry of cross sections and comparing parameters with variety of models, it could be suggested that the Khaneh Sorkh Anticline is a detachment fold in the thrust fault-related folds. Finally,geometry of faulted detachment fold and analysed kinetic evolution is valid for Khaneh Sorkh Anticline based on the proposed model. Manuscript profile